Various water tanks and the like are desirably lined with a flexible plastic barrier to prevent corrosion of the tank, or the leaching of undesirable substances. This is especially the case when the tank body is made of steel which, apart from the corrosion problem, can exhibit significant advantages over other materials.
As described in U.S. Pat. No. 4,537,329, a system is provided for connecting a plastic tank lining to a penetration fitting which forms an opening through a tank wall. By this present invention, an improved structure for a tank lining system is provided which is easier to assemble, and which provides an air and water tight seal between the liner and the tank without the use of sealants or direct compression gaskets. A direct compression gasket is a gasket which is under constant compression. A disadvantage of such a gasket is that, over a period of time it can take a compression set due to the constant pressure and can lose effectiveness.
Likewise, the time and effort required to place the tank lining system into a tank is reduced in this invention over prior art systems, while excellent results of sealing and durability are achieved.
Additionally, The Culligan International Company has sold a tank lining system where a yoke is required. By this invention such a yoke is eliminated.